“They could generate revenue that exceeds the amount of money needed to save every threatened species on the planet,” Dr Holden said.

“In the US alone, 2.7 million people die each year, with an estimated funeral revenue of US$19 billion – far more than the estimated $3-$5 billion required to protect every threatened species listed by the international Union for the Conservation of Nature.

“While not every threatened species can benefit directly from conservation burials, the hypothetical revenue demonstrates substantial potential for increased biodiversity.”

Dr Holden said Halloween was the perfect time to urge the public and government and non-government organisations to contemplate how death could support future life on earth through conservation from the grave.

“If conservation burials became as commonplace as similar types of after-death charity, such as organ donation, the biodiversity benefits would be enormous,” he said.